End closures for drums and equivalent containers

ABSTRACT

1,111,679. Cans, drums &amp;c. RHEEM INTERNATIONAL Inc. 29 Oct., 1965 [16 Dec., 1964], No. 45872/65. Heading B8D. In a sheet metal drum having peripheral corrugations, the ends are closed by members attached to the end walls by double-locked seams 18 and each comprising a flat annular portion 19, a step 23, and a central flat portion 26 connected to the step by a convex annular portion 27. In Fig. 3 (not shown), the step is in the form of a convex bead (44). Absolute, and comparative in terms of the outside diameter of the chime 18, dimensions are given for a practical drum embodiment.

Sept. 5, 1967 A. F. GERLOVICH END CLOSURES FOR DRUMS AND EQUIVALENT CONTAINERS Filed Dec. 16, 1964 W y T 5 N W EM 0 W T /G N E Y B F.

United States Patent O 3 339,793 END CLOSURES FOR DRUMS AND EQUIVALENT CONTAINERS Albert F. Gerlovich, Fanwood, N.J., assignor to Rheem Manufacturing Company, New York, N.Y., a corporation of California Filed Dec. 16, 1964, Ser. No. 418,768 6 Claims. (Cl. 220-66) ABSTRACT OF THE DISCLOSURE This disclosure describes a metal end closure for large drums of the type used to store and transport flowable materials such as petroleum and chemical products. The end closure includes an outer cylindrical chime for securing the closure over an end opening of a drum, a flat annular region inwardly adjacent and perpendicular to the chime, a knuckle interconnecting the chime and annular region, a central circular region, and a shallow longitudinally offset circumferential strengthening section Interconnecting the fiat annular region and the central circular region. The strengthening section includes a step portion which is inclined radially inwardly and longitudinally from the inner end of the flat annular region, and the central circular region has a central flat circular portion and a convex annular portion extending between the flat circular portion and the strengthening section. It has been found that a drum end closure of this configuration is not subject to radial creases and fractures due to rough handling or transportation of the drum.

This invention relates to metal containers such as drums, and is more particularlydirected to improved end closures therefor which may be constructed of medium gauge steel, such as 18 gauge, and yet will not crack or leak when the drum is loaded and subjected to'repetitive impacts of the type occurring, for example, during transport of the drum over long distances by truck.

Metal drums, or the like, having a wide range of sizes have long been utilized for storing and shipping pourable or other products. In general such drums have included a cylindrical body and heads respectively secured to the opposite ends of the body to provide end closures therefor. Typically, each head includes a circumferential knuckle extending arcuately longitudinally outwardly into the chi-me which in turn curves radially outwardly and longitudinally inwardly at its upper end over the rim of the body to terminate in a double lock seam therewith. In addition, the central portion of each head radially inwardly of the knuckle is frequently domed to form a bilge for the purpose of increasing the capacity of the drum.

It has been found that drums of the foregoing type having bodies and heads both constructed of medium gauge steel, such as 18 gauge, as designed to have a capacity of for example 55 gallons, experience head failure under various circumstances. Head failure of these drums is particularly prevalent where the drums contain liquid weighing in excess of about 500 pounds and the drums are shipped by truck. During transit of the drums, the bottom heads thereof develop cracks in the vicinity of the knuckles and chimes which give rise to leaks. The cracks typically extend radially outward from points one to two inches from the chime straight to the knuckle radius and longitudinally outward along the chime to terminate at the seam radius. In addition, circumferential cracks are often exhibited in the vicinity of the knuckle which intersect the radial cracks. Apparently, the cracks are due to fatigue failure, the heads progressively cracking over a period of time under repetitive stresses. In this regard, it is presumed that radial bulges or creases are formed in the bottom head of the drum in the vicinity of the knuckle due to the impact force of the liquid acting thereon when, for example, the drum is dropped during the loading of a truck, the truck runs over some large chuck holes or curbs, etc. The creases act as detrimental stress risers and result in flexing of the bottom head. Thereafter continued flexing of the head due to vibration of the liquid during the remainder of the route causes the creases or adjacent areas to crack by fatigue.

It is therefore an object of the present invention to provide an improved head for drums or the like which, without resorting to a relatively heavier gauge steel, will not crack under the conditions of impact and vibration noted hereinbefore.

Another object of the invention is to provide a drum head of the class described having a novel construction in the vicinity of the knuckle and chime which serves to reenforce same and prevent the formation of radial creases or bulges therein.

Still another object of the invention is the provision of a drum head of the class described which is relatively rigid and capable of holding bilge height to a given dimension.

It is a further object of the invention to provide a drum head of the class described which, while being highly effective may yet be readily manufactured.

The invention possesses other objects and features of advantage, some of which, with the foregoing, will be set forth in the following description of the preferred form of the invention which is illustrated in the drawing accompanying and forming part of the specification. It is to be understood, however, that variations in the showing made by the said drawing and description may be adopted within the scope of the invention as set forth in the claims.

FIGURE 1 is a side elevation view of a drum having improved heads in accordance with the present invention.

FIGURE 2 is an enlarged fragmentary sectional view taken at a diametric plane through a head of the drum of FIGURE 1.

FIGURE 3 is a view similar to FIGURE 2 of a modified form of head in accordance with the invention.

FIGURE 4 is a view similar to FIGURE 2 of another modified form of head in accordance with the invention. Referring to FIGURE 1, there will be seen to be provided a metal drum 11 including a cylindrical tubular body 12 having similar top and bottom heads 13 secured in closing relation to the opposite ends thereof. The body bent portion-s 16 12 is preferably provided with a plurality of peripheral swedges 14 to strengthen the body in a conventional manner. In addition, the ends of the body are provided with radial outward and longitudinally inward U-shaped adapted to cooperate with complementary radial inward and longitudinally outward U- shaped bent portions 17 provided at the peripheries of the heads 13 in the formation of double locked seams 18 serving to secure the heads to the body.

As previously noted, where conventional heads have been employed in drums, there has been a severe tendency for the bottom head to crack in the vicinity of the chime when the drum, filled with liquid, is subjected to impact andvibration of the type generated during transport of the drum by truck. This is apparently due to conventional heads being sufficiently flexible in the vicinity of the chime that the impact of liquid contained in the drum produces radial creases or bulges adjacent the chime. Continued flexing of the head by repetitive vibrational stresses or the like then cracks the bulges or adjacent areas by fatigue.

The present invention overcomes the above problem by providing heads having a novel reenforcing configuration in the region of the head inwardly adjacent the chime.

As a result, thisregion of the head is highly resistant toflexure and does not bulge or crease upon impact of liquid contents of the drum with the head. Since the bulges are prevented from forming, the head does not crack.

In basic respects, the improved head of the present invention includes a flat annular region in perpendicular inwardly adjacent relation to the chime and merging smoothly therewith through a small radius circumferential knuckle. The flat region terminates inwardly in a shallow longitudinally offset circumferential strengthening section which in turn merges inwardly with the central portion of the head. The central portion is preferably bilged and provided with a flat center being blended with a radius that forms the bilge to the radius of the strengthening section. Such configuration has been observed to be highly resistant to flexing and radial bending.

Considering now the invention in greater detail as to the preferred embodiment thereof depicted in FIGURES 1 and 2, it is to be noted that the head 13 is provided with a fiat annual region 19 of the type mentioned above. The flat region terminates outwardly in a small radius cirmumferential knuckle 21 which in turn extends longitudinally outward into the longitudinal portion of the chime 22, which at its outer end extends radially outward and longitudinally inward to terminate in the U-shaped bent portion 17. The flat region 19 terminates inwardly in a shallow angular step 23, which in the present instance is inclined radially inward and longitudinally outward with respect to the drum body 12, and comprises the strengthening section of previous mention. The step in turn terminates inwardly in a bilge 24, which it is of importance to note includes a flat circular central portion 26 and convex annular portion 27 extending between portion 26 and step 23. The flat central portion 26 is slightly inwardly longitudinally spaced from the outer end of the chime 22.

With regard to the preferred relative dimensions of the various portions of the head 13, same may be conveniently expressed in terms of the head diameter, D. The radial width of the fiat annular region 19 is advantageously about D, while the radius of knuckle 21 is about ,6 D. The longitudinal extent of step 23 about D, and this step is preferably at an angle of 45 to the flat region. It will be thus appreciated that unlike a conventional servi, the step is substantially more shallow. A longer step leaves room for bulges to form whereas too shallow of a step does not rigidize the area sufiiciently. the fiat central portion 26 is about D while the radial extent of the annular portion 27 is D. The longitudinal distance between the flat central portion 26 and flat annular region 19 (bilge height) is about & D and the longitudinal distance between annular region 19 and the outer end of the chime 22 is /144 D. The radius of curvature of the convex annular portion 27 is 2 D. It has been found in practice that heads in accordance with the present invention having the foregoing relative dimensions and constructed of sheet metal of a medium gauge in a range of about 22 to 16 gauge, do not exhibit cracking of the type previously discussed.

Considering now a specific example of a drum 11 having heads 13 in accordance with the present invention and designed for a capacity of 55 gallons, it should be noted that the body 12 has a 22 /2" inside diameter, 23 outside diameter at the swedges 14, and a length of 34%". The head diameter between the outside of the chime 22 is then 22 /2". The longitudinal distance between the flat annular region 19 and outer end of the chime is and the radius of knuckle 21 is A". The radial extent of flat annular region 19 is /2 and the longitudinal extent of step 23 is A", which step is at an angle 45 to the fiat annular region. The fiat circular central portion 26 has an 8" diameter and the radius of curvature of convex annular region 27 is 58 /2". The bilge depth is then 43". The particular drum just described may be made of any gauge sheet steel in a range of 22 through 16 gauge, or any combination of these gauges.

Referring now to FIGURE 3, there is illustrated a modified form of head 28 in accordance with the present invention which is generally similar to the head 13 previously described except that the instant head is not bilged. More particularly, the head 28 includes a chime 29 terminating at its outer end in a U-shaped bent portion 31 for facilitating securance of the head to the body of a drum by means of a double seam joint. The head is provided with a flat annular region 32 inwardly adjacent and perpendicular to the chime, which annular region merges smoothly with the chime through the intermediary of a small radius circumferential knuckle 33. To this extent the head 28 is similar to head 13. However, in the design of head 28, the flat annular region 32 terminates inwardly in a flat central circular portion 36. As in the case of the previously described embodiment, the step 34 and flat annular region 32 provide an area that is highly resistant to creasing or bulging, and accordingly is effective in preventing the formation of cracks.

Although the longitudinally offset circumferential strengthening section has been provided as a shallow inclined step in the embodiments of the head hereinbefore described in detail, it will be appreciated that various alternatives may be employed such as that depicted in FIGURE 4. In this regard, a head 37 is provided which, as in the case of the heads 13 and 28, includes a chime 38 terminating at its outer end in a U-shapcd bent portion 39 for facilitating securance of the head to the body of a drum by means of a double seam joint. The head is provided with a flat annular region 41 inwardly adjacent and perpendicular to the chime, which annular region outwardly merges smoothly with the chime through the intermediary of a small radius circumferential knuckle 42. As in the case of the head 13, head 37 includes a central bilge 43 preferably having a flat center and convex annular outer portion. In the present instance, however, the strengthening section is provided as a circumferentially extending relatively shallow outwardly convex bead 44 interconnecting the inner portion of flat annular region 41 and the bilge 43. The head is inclined outwardly a short distance from the flat annular region to, in turn, irecurve inwardly and merge smoothly with the bilge. The configuration of 'head 37 has likewise been found to be highly effective in preventing the formation of cracks.

What is claimed is:

1. A drum head including a chime having a cylindrical portion with an outside diameter D, a flat annular region inwardly adjacent and perpendicular to said cylindrical portion of said chime, said annular region having a radial extent of about D, a knuckle interconnecting said flat annular region and cylindrical portion of said chime, said knuckle having a radius of curvature of about A D, a longitudinally offset circumferential strengthening section which includes an angular step portion inclined radially inwardly and longitudinally outwardly from the interior of said flat annular region, said step portion having an angle of about 45 with respect to said flat annular region and a longitudinal extent of about D, a central fiat circular portion having a diameter of about D, and a convex annular portion interconmeeting said flat circular portion and said strengthening section, said convex annular portion having a radius of curvature of about 2 4 D, said flat central portion longitudinally spaced from said flat annular region by a distance of about D, said flat annular region longitudinally spaced from the outer end of said chime by a distance of about 7 D.

2. A drum head according to claim 1, wherein said outside diameter D of said cylindrical portion of said chime is 22 /2", said flat annular region has a radial extent of /2, said knuckle has a radius of curvature of A", said step portion has a longitudinal extent of A, said flat circular portion has a diameter of 8", said convex annular portion has a radius of curvature of 58 /2" said flat central portion is longitudinally spaced from said flat annular region by said flat annular region is longitudinally spaced from the outer end of said chime by and said head is fabricated from sheet metal having a gauge in a range of 22 through 16 gauge.

3. A drum comprising a cylindrical tubular body having radially outward longitudinally inward U-shaped bent portions at its opposite ends, and a pair of circular heads respectively disposed in closing relation to the opposite ends of said body, said heads respectively having radially inward longitudinally outward U-shaped bent portions engaging said bent portions of said body in double seam joints, said heads each having a chime extending radially inwardly and longitudinally inwardly from the bent portion of the head, a flat annular region radially inwardly adjacent and perpendicular the longitudinally inner end of said chime, a small radius circumferential knuckle interconnecting said flat annular region and said chime, a longitudinally offset circumferential strengthening section which includes a shallow step portion radially inwardly and longitudinally outwardly inclined from the inner end of said flat annular region, a flat circular central region, and a curved convex annular region interconnecting said central region and said strengthening section.

4. An end closure for a container including a cylindrical chime, a flat annular region inwardly adjacent and perpendicular to said chime, a knuckle interconnecting said chime and annular region, a central circular region, and a shallow-longitudinally offset circumferential strengthening section interconnecting said flat annular region and central circular region, said strengthening section including a step portion inclined radially inwardly and longitudinally from the inner end of said flat annular region, and said central circular region having a central flat circular portion and a curved convex annular portion extending between said fiat circular portion and said strengthening section.

5. An end closure according to claim 4, wherein the outside diameter of said chime is D, said flat annular region has a radial extent of about 4 D, said knuckle has a radius of curvature of about ,4, D, said portion has a longitudinal extent of about D and is at an angle of about to said flat annular region.

6. An end closure according to claim 4, further defined by said strengthening section comprising a circumferentially extending shallow outwardly convex bead.

References Cited UNITED STATES PATENTS Re. 3,757 12/1869 Wilson 22072 1,963,795 6/1934 Lang 220-66 1,987,817 1/ 1935 Burns 22066 2,012,213 8/1935 Young 22066 2,810,492 10/1957 Bergen et al 22067 X 3,150,765 10/1963 Creegan 22066 X FOREIGN PATENTS 339,732 4/ 1904 France. 802,327 2/1951 Germany.

THERON E. CONDON, Primary Examiner. MARTHA L. RICE, Examiner. 

3. A DRUM COMPRISING A CYLINDRICAL TUBULAR BODY HAVING RADIALLY OUTWARD LONGITUDINALLY INWARDLY U-SHAPED BENT PORTIONS AT ITS OPPOSITE ENDS, AND A PAIR OF CIRCULAR HEADS RESPECTIVELY DISPOSED IN CLOSING RELATION TO THE OPPOSITE ENDS OF SAID BODY, SAID HEADS RESPECTIVELY HAVING RADIALLY INWARD LONGITUDINALLY OUTWARD U-SHAPED BENT PORTIONS ENGAGING SAID BENT PORTIONS OF SAID BODY IN DOUBLE SEAM JOINTS, SAID HEADS EACH HAVING A CHIME EXTENDING RADIALLY INWARDLY AND LONGITUDINALLY INWARDLY FROM THE BENT PORTION OF THE HEAD, A FLAT ANNULAR REGION RADIALLY INWARDLY ADJACENT AND PERPENDICULAR THE LONGITUDINALLY INNER END OF SAID CHIME, A SMALL RADIUS CIRCUMFERENTIAL KNUCKLE INTERCONNECTING SAID FLAT ANNULER REGION AND SAID CHIME, A LONGITUDINALLY OFFSET CIRCUMFERENTIAL STRENGTHENING SECTION WHICH INCLUDES A SHALLOW STEP PORTION RADIALLY INWARDLY AND LONGITUDINALLY OUTWARDLY INCLINED FROM THE INNER END OF SAID FLAT ANNULAR REGION, A FLAT CIRCULAR CENTRAL REGION, AND A CURVED CONVEX ANNULAR REGION INTERCONNECTING SAID CENTRAL REGION AND SAID STRENGTHENING SECTION. 